Available Utilities
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False Link Aggregation Alerts
The following sections explain false link alerts caused by a slow Link Aggregation and provides
a procedure for correcting the issue.
Symptoms
If you experience problems with Link Aggregation during a power up, or if all the ISIS Engines
are restarting, the following could be happening.
•
Slow Link Aggregation (Trunking) setup — When the Link Aggregation feature is taking a
longer than expected to complete. This setup process can viewed by opening to the Avid
ISIS Switch Blade Agent page > System tab, and click on the “View current settings” in the
left pane. When the process is complete, the status message “Enabled Fully Operational”
should be displayed for any VLAN that has a correctly defined and enabled Link
Aggregation (trunk) group.
While the Link Aggregation is setting up, the ISIS ports that are in the Link Aggregation
group form an open loop in the network that can cause problems with the connecting
Ethernet switches. When using the Cisco 4900. the longer the Link Aggregation feature
takes to come up, the longer the loop exists and is more likely to cause a problem.
•
Fake Link Alert — A link alert is a message sent to the ISIS agent page and the Management
Console letting you know that the given 10 Gig port is not functioning as expected. A fake
link alert is when this link alert message is display when the port is working correctly. This
could also be thought of a false positive. This fake link alert can occur in ISIS 7000 v 2.4 and
earlier, this fix in the ISIS v4.0 release an later.
Displayed Link Alert Message
Use the following methods to determine if the displayed link alert message is a real problem or a
false positive.
To verify the link alert message:
1. Run diagnostics, and look at the “Details for test: (18) port link information.” The
information in this section of the diagnostic output comes directly from the hardware and
tells you the correct status on whether the switch port is up or down for all the ports in the
stack.
2. Check the stacking data for the Engine displaying the link alert message. The information in
the stacking display comes directly from the hardware and tells you the correct status on
whether the switch port is up or down for the port in question.
a.
Go to the ISIS Switch Blade Agent page.
b.
Click System tab.
c.
Click Overview in the left pane.
